Satellite applications
Satellite technology offers effective technical and economic solutions for the establishment of state-of-the-art telecommunication networks, providing trunk telephony and data, direct digital radio and TV and broadband services to fixed and mobile user terminals. Satellites are also key elements in emergency telecommunications, meteorology, global positioning systems, environmental monitoring and communication services, that ensure safety of life on land, at sea and in the skies. Accordingly, the demand for satellite capacity has grown, and with it, the demand for use of the orbit/spectrum resource. As the options for such use are limited by a combination of technical and economic factors, the problem of resource scarcity has arisen, along with the concern that the development of new satellite applications and networks may be held back.

The successful introduction of any radio system thus depends on the availability of radio frequency spectrum as a valuable common resource. The development of satellite communication has led to the appearance of a new, invisible international resource – the geostationary-satellite orbit (GSO). At present, most communication satellites describe a circular orbit in the plane of the Earth’s equator at an altitude of about 36000 km, resulting in a 24-hour period of revolution around the centre of the Earth. They are synchronous with the Earth’s rotation and would appear to be motionless in relation to a reference point on the Earth’s surface. This characteristic enables the satellite to provide permanent coverage of a given area, which simplifies the design of earth stations, as they are not required to track such satellites. The latter are thus located on the GSO and are designated as geostationary satellites. The very characteristics of the GSO mean that it is finite, and subject to possible congestion but not depletion as a common resource.

Various other satellite systems use non-geostationary satellites (non-GSO), mainly for space research, earth exploration and radionavigation applications. They mostly involved low-Earth orbit (LEO) satellites, designed to operate at altitudes between 400 and 1500 km, and to a more limited extent medium-Earth orbit (MEO) satellites, orbiting at altitudes between 7 000 and 12 000 km. For non-GSO satellites the problem of orbit scarcity is less crucial, as greater flexibility exists in designing the orbital characteristics of the constellations. This flexibility however would decrease for systems with numerous non-GSO satellites providing applications in e.g. the mobile or fixed-satellite services.

International space regulatory framework
International management of the use of the radio-frequency spectrum and orbits is entrusted to the International Telecommunication Union (ITU). The ITU Member States have established a legal regime, which is codified by the ITU Constitution and Convention, complemented by the Radio Regulations (RR) which enshrine the main principles and lay down the specific regulations governing the registration of satellite network frequency assignments. The Radio Regulations are revised partially or, in exceptional circumstances, completely by world radiocommunication conferences (WRCs) and constitute a binding international treaty (Radio Regulations, 2008).

The Radio Regulations constitute the unique international basis for achieving an interference-free - or rather interference-controlled – environment for satellite operation and guaranteeing equitable access to use of the natural resources of the frequency spectrum and GSO. Two major mechanisms for the sharing of orbit and spectrum resources have been developed and implemented – the A priori planning procedures which include the Allotment Plan for the fixed-satellite service and the Plan for the broadcasting-satellite service and the associated Plan for feeder links (planned services) and the Coordination procedures (unplanned services). The right to use a satellite position and associated frequency bands in unplanned services is acquired through negotiation (“coordination before use”) with the administrations concerned by actual use of the same portion of the orbital segment and associated spectrum. Completion of the registration procedure, including the coordination and recording of frequency assignments in the Master International Frequency Register (MIFR), establishes the rights and obligations of administrations in the domain of orbit/spectrum management, the aim being to prevent possible loss of investment, customers and revenue by minimizing the capacity that remains unusable due to potential interference.

Concerns regarding the application of the registration procedures
The current regulatory procedures were developed back in the 1970s, and they have successfully served their purpose since then. However, as the occupancy of the resources increased and demand for satellite services grew, a somewhat abnormal behaviour emerged in international satellite network registration.
Independent information on the real use of the orbit/spectrum resource has shown some divergence from the corresponding information submitted by administrations to ITU. Indeed, “paper satellite” issues - or more precisely, recorded frequency assignments that are fictitious - still exist. One reason for this is that administrations have no real incentive to give up underused orbit/spectrum resources or update their satellite network parameters at the stage of notification and recording of assignments in the MIFR in order to accurately reflect their planned operations. Rather, the incentive is quite strong to reserve (and thus freeze) spectrum regardless of real future needs, thus de facto denying access to new entrants.

The enforcing mechanisms that exist at present to ensure that a satellite system is operating in accordance with recorded parameters are based mainly on goodwill of administrations. When goodwill is linked to financial consequences, enforcing mechanisms of this kind tend to be disregarded.

The Bureau also recently witnessed an attempt in which a satellite was launched, placed on the GSO, brought into use and operated with no prior coordination with existing satellite networks and no information concerning the associated ITU satellite network filing. The Bureau is extremely concerned and alarmed at this kind of fait accompli situation, in which a satellite is operated in contravention of the ITU Constitution, particularly No. 196, and of No. 18.1 of Article 18 of the Radio Regulations on Licences, and this without a responsible administration and by an unknown operating agency not duly authorized by an ITU Member State. The Bureau is also worried about possible cases of harmful interference caused by such satellites to frequency assignments to satellite networks or terrestrial service stations duly recorded in the MIFR, with no possibility for the Bureau to apply Section IV of Article 15 of the Radio Regulations to settle the problem.

WRC-11 and beyond
The future development of satellite communications is closely bound up with the international regulatory procedures, which as things stand may be seen as placing some limitations on the development of new satellite projects or as being jeopardized by certain behaviour. There is thus a pressing need to take steps to guarantee and increase efficiency in the use of the orbit/spectrum resource. The international regulatory framework for registering satellite networks must be improved, and the improved framework must be operative or ready to be operative by WRC-11 if ITU is to maintain its credibility and to remain fully relevant to the satellite community.
Indeed, there is no place other than ITU for management of the radio spectrum, no place other than the WRC for diplomatic wrestling and all-night negotiation marathons producing win-win agreements, but any such agreements can only be of value if the space community is inventive and creative enough to offer value-added services and make efficient use of the scarce orbit/ spectrum resource in providing those services.

ITU is ‘committed to connecting the world’ and satellite communication systems have an enormous potential to offer promising high-capacity transmission capabilities in this regard. To achieve that goal, however, governments, international organizations and the private and public sectors must continue to enable ITU to carry out its vital work of recording frequency assignments in the MIFR, thus ensuring that frequencies and orbital positions are compatible and do not result in radio interference.
 

Yvon HENRI is Chief of the Space Services Department (SSD) at the Radiocommunication Bureau of the International Telecommunication Union (ITU), in Geneva (Switzerland). Before joining ITU in 1995, he has held various management positions at France Telecom (Paris, France) and INTELSAT (Washington DC, USA) and has been involved in the satellite business for more than 20 years.

ITU is the leading United Nations agency for information and communication technologies. As the global focal point for governments and the private sector, ITU's role in helping the world communicate spans 3 core sectors: radiocommunication, standardization and development. ITU also organizes TELECOM events and was the lead organizing agency of the World Summit on the Information Society.
ITU is based in Geneva, Switzerland, and its membership includes 191 Member States and more than 700 Sector Members and Associates.
Within the ITU, the Space Services Department is responsible for managing the procedures for registration of all space system frequency assignments (satellite and Earth and radioastronomy stations) in accordance with the ITU Constitution and Convention, including the Radio Regulations. The Department also provides assistance and support to administrations, operators and frequency assignment customers on all issues related to space service frequency management.

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A one-day workshop on 'The efficient use of spectrum/orbit resource' is scheduled to take place in Geneva on 7 May 2009 (date to be confirmed). Further information regarding this workshop will be provided on the BR website and on a future issue of the ITU-R e-Flash.

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